The subject matter of this invention is a swivel coupling for connecting a hose containing a plurality of conduits to a handpiece such as a dental handpiece having like conduits for drive air, secondary air and water. In addition, the coupling of this invention includes a lamp for illumination of the handpiece work area, such lamp being adapted for swivel connection to electrical conductors extending through the hose.
The most relevant prior art that I know of is U.S. Pat. No. 4,398,885, issued Aug. 16, 1983 to Loge and Bareth. This patent discloses a dental handpiece including an illumination lamp for illuminating an optical fiber bundle which in turn illuminates the work area. The handpiece is swiveled relative to to its connection to a supply hose. The lamp appears to be stationary with respect to the hose coupling and the handpiece is rotatable relative to the lamp.
The present invention may be summarized as a dental handpiece swivel coupling with a handpiece portion attached to the handpiece and a hose portion attached to a supply hose, the handpiece portion being swivelably mounted on the hose portion. The handpiece portion of the coupling includes an illumination lamp which makes electrical contact with an annular commutator on the hose portion, electrical continuity thus being maintained while the handpiece portion of the coupling swivels relative to the hose portion of the coupling. Exhaust air from a turbine in the handpiece is directed over the lamp for heat removal.